ehrenpreis



March 1 7, 1925. 7 1,530,311

J. EHRENPREIS TALKING MACHINE Filed May 5, 1911 s Shets-Sheet 1 March 17, 1925.

J. EHRENPREIS Filed May 5, 1917 TALKING MACHINE 3 Sheets-Sheet 2 March 17', 1925. 1,530,311

J. EHRENPREIS TALKING MACHINE Filed May 5, 1917 3 Shets-Sheet 5 Patented Mar. 17, 1925.

UNITED STATES PATENT OFFICE.

JOHN EERENPBEIS, OF DUIBUQUE, IOWA, ASSIGNOR TO THE BRUNSWIGK-BALKE-COL- LENDER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF DELAWARE.

wamzrnc momma Application filed Kay 5, 1917. Serial No. 166,684.

To all whom it may concern.

Be it known that I, J on Ernmnrnnrs, a citizen of the United States, residing at Dubuque, in the county of Dubuque and State of Iowa, have invented certain new and useful Improvements in Talking Machines, of which the following is a specification.

' This invention relates to talking machines embodying a novel sound amplifier.

The primary object of my invention is the provision in a talking machine of a. cabinet type, of an amplifier, the cross-sectional outline of which is rounded, whereby the sound waves are permitted to expand spherically Without interference by plane surfaces and sharp corners and which is sufficiently compact to be mounted in the space usually alloted to the amplifier in a modern talking machine cabinet.

A further object of my invention is the provision in a cabinet talking machine of means for limiting the amplitude of the vibrations set up in the walls of the amplifier, whereby the tone quality is preserved and the sounds issuing from the amplifier are rendered more natural.

A further object of my invention resides in the provision of a wood amplifier of novel construction and resonating properties.

I Further objects and advantages of my invention will be apparent as it is better understood by reference to the following specification when read in connection with the accompanying drawing, illustrating a preferred embodiment thereof, in which Fig. 1 is a front elevation of a talking machine according to my invention with a portion of the grill removed;

Fig. 2 is a side. elevation, partially in section, of the talking machine;

Fig. 3 is a detail in perspective of the amplifier;

Fig. 4 is a longitudinal section through the amplifier;

Fig. 5 is a transverse section on the line 5-5 of Fig. 4;

Fig. 6 is a horizontal section through the talking machine cabinet;

Fig. 7 is a detail in section, illustrating the support for the mouth of the amplifier;

Fig. 8 is a plan view of a blank from which the bell portion of the amplifier is formed and Fig. 9 is an edge view'of the blank, the layers of veneer being separated at one end for the purpose of illustration.

Prior to the introduction of the'modern cabinet type, talking machines were provided with exterior horns or amplifiers which were in certain instances constructed of sections of wood secured together. Cab-' inet talking machines have been provided w1th metal amplifiers of rounded or clrcular cross-sectional outline. More commonly they have been provided with wood amplifiers having plane sides intersecting at angles. Both the metal and wood amplifiers as above described present certain disadvantages. The resonance of the metal amplifiers is not of a character best adapted to preserve the bone quality of the sounds issuing therefrom. The wood amplifiers, since they present plane surfaces and angles to the normal spherical sound waves, produce a harshness of tone which is not satisfactory. Her-etcfore-it has been impossible to construct a wood amplifier of rounded cross-sectional outline which could be mounted in the space usually allotted to the amplifier in a modern cabinet machine and yet provide a sound passage of sufficient length to insure proper amplification. I have perfected a wood amplifier of rounded cross-sectional outline adapted for use in talking machines of the cabinet type. I have discovered that the best results are obtained when the amplitude of the vibrations set up by the sounds in the walls of the amplifier are limited or restrained by mounting the amplifier in the .manner indicated in the accompanying 12 having an opening corresponding in outline to the mouth of the amplifier and filling all of the space surrounding the mouth of the amplifier between the top board 7 and the partition 8 and the side walls of the cabinet. Thus sounds emanating from distort the reproduced sounds.

the motor (not shown) are confined within the space surrounding the amplifier. The amplifie'r is preferably fastened at its mouth by screws 13 to blocks 14 behind the front board 12 and fast to the walls of the cabinet The screws 'may, however, be omitted, the mouth of the amplifier resting snugly in the opening in the front board. Thus the amplitude of the vibrations set up in the walls of the amplifier is materially modified and prevented from reaching a point where they The usual grille 15 is arranged in front of the front board 12 and covers the mouth of the am- My improved ainplifier includes a nonvibratory neck portion 16 constructed of blocks of wood glued or otherwise fastened together. The blocks before being glued together are routed to provide in each, half and 21, respectively. The plies 19 and 21,

are arranged so that the grain of the wood extends longitudinally of the finished ainplifier while the .grain of the ply 20 extends circumferentially about the amplifier. The veneer is first cut to the form indicated in Fig. 8 and is then bent until at the mouth the edge has the contour of an ellipse. The inner end has also the contour of an ellipse but approaches more nearly a circle. The free edges of the veneer are rabbeted, as indicated at 22 in Fig. 5, and glued together. The joint is then covered with adhesive tape 23 which insures against possible separation of the edges of the veneer. The inner end of the bell portion fits into the lower end of the neck portion 16 of the amplifier and is glued or otherwise fastened therein. The bottom of the bell portion is substantially horizontal while the top inclines upwardly from the neck so that the axis of the opening in the smaller end of the bell portion is belaow the axis of the opening in the larger en When complete my improved amplifier provides a smooth sound passage which is circular at its smaller end and gradually becomes elliptical in cross-section. Thus the sound waves are permitted to advance in the amplifier and expand spherically. without interference by plane surfaces and angular corners as in the wood amplifiers of the prior cabinet talking machine art. The

amplifier provides a sound passage of sufii the reproduced sounds. It will be seen that the bell portion 18, or, as it may be expressed, the bell' portion 18 is relatively flexible in respect to the neck. By this arrangement I find that greatly improved results are obtained, it being understood that it is best to secure the mouth of the bell portion to the cabinet to prevent excessive vibration therein. The rigid neck prevents absorption of undesirable vibrations which cause what is generally known as scratch, therein, while the relatively flexible bell portion provides for their absorption in that part of the amplifier. If absorption of these sounds was provided for in the neck, where all sound waves are concentrated, it would be diflicult to prevent absorption of other sound waves which it is desired to reproduce, but by providing the flexible bell portion in combination with the rigid neck, I have found that this bell portion provides a selective absorption of the undesirable sounds which 'form the so-called scratch without absorbing sound waves which it is desired to reproduce.

From the foregoing it will be understood that I have perfected an improved amplifier for talking machines and that my amplifier is mounted in the machine in a novel manner to produce new and desirable results. In the practical operation of my invention 1 find that the reproducing quality of the instrument is greatly improved by the substitution of the amplifier described herein for an amplifier of rectangular cross-section which I have heretofore used.

It will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the'invention or sacrificing any of its material advantages. the form herein-before described being merely a preferred embodiment thereof.

I claim:

1. An all-wood sound amplifier for talking machines comprising a solid wood neck having a curved bore therein, and a bell portion connected to the neck and consisting of a veneer blank bent to a rounded cross sectional contour.

2. An all-wood sound amplifier for talking machines comprising a solid wood neck having a curved bore therein, and a bell portion connected to the neck and consisting of a veneer blank bent to a rounded cross-sectional contour, the inner and outer plies of said veneer having the grain directed longitudinally of the bell portion and the intermediate ply having the grain directed circumferentially about the bell portion.

3. A sound amplifier for talking inachines comprising a rigid neck having a bore therein, and a bell portion connected to the neck and consisting of a veneer blank back, bottom and bent to a rounded cross-sectional contour and having its edges united, the interior surface of said bell portion being smooth and unbroken and extending throughout in straight diverging lines longitudinally and in curved lines transversely.

4. An all-wood sound amplifier for talking machines comprising a rigid neck having a bore therein, and a bell portion connected to said neck and comprising a veneer blank bent to a rounded cross-sectional contour, the bottom of said bell portion being substantially horizontal and the top of said bell portion inclining upwardly from said neck.

5. An all-wood sound amplifier for talking machines comprising a rigid neck having a bore therein, and a bell portion connected to said neck and comprising a veneer blank bent to a rounded cross-sectional contour. the axis of the opening in the smaller end of said bell portion being located below the axis of the opening in the larger end thereof.

6. An all-wood sound amplifier for talking machines comprising a solid wood neck having a curved bore therein, and a bell portion connected to said neck and comprising a veneer blank bent to a rounded crosssectional contour, the smaller end of said bell portion being substantially circular in cross-section and the larger end of said bell portion being elliptical in cross-section with the major axis substantially horizontal.

7. An all-wood sound amplifier for talking machines comprising a solid wood neck having a curved bore therein, and a bell portion connected to said neck and comprising a veneer blank bent to a rounded crosssectional contour, the smaller end of said bell portion being substantially circular in cross-section and the larger end of said bell portion being elliptical in cross-section, and the intermediate portion merging gradually from a circular cross-section to an elliptical cross-section with the major axis substantially horizontal.

8. A talking machine comprising a cabinet having a chamber therein, said chamber having a top board with an opening therein, a front with an elliptical opening therein, asides, and an all-wood amplifier in said chamber wood neck provided with a curved bore and having its upper end arranged in the opening in the top board, and a bell portion formed of a veneer blank bent to a rounded cross-sectional contour, the smaller end of said bell portion being substantially circular in cross-section and connected to and supported by the lower end of the neck and the larger end of said bell portion being elliptical in cross-section with the major axis substantially horizontal and supported in the opening in the front of said chamber. 9. A talking machine comprising a cabinet comprising a solid having a chamber therein, said chamber having a top board with an opening therein, a front with an opening therein, a back, bottom and sides, and an all-wood amplifier in said chamber comprising a neck having a curved bore therein and supported in the opening in said top board, and a bell portion formed of a veneer blank bent to a rounded cross-sectional contour, the smaller end of, said bell portion being connected to and supported by the lower end of the neck, and means for securing the larger end of the bell portion in the opening in the front of the chamber and comprising blocks en aging walls of the chamber and the amplifier for limiting the amplitude of the vibrations set up therein.

10. An all-wood sound amplifier for talking machines comprising a bell portion con-' and having its small en'd connected to onev side of said block to form a continuous sound passage through the bell and block and having a smooth and unbroken interior surface.

12. A talking machine comprising a cabinet having a chamber therein, an amplifier disposed in said chamber and comprising a relatively rigid wood block and a relatively flexible bell, the block having a curved sound passage therethrough, the bell consisting of a wood veneer blank bent to a rounded cross-sectional contour and having its small end connected to one side of said block to form a continuous sound passage through the bell and block and having a smooth and unbroken interior surface, the block being secured in place in the said chamber, and the large end of the bell being secured in a wall of the chamber.

13. A talking machine comprising a cabinet having a chamber therein, and an all wood sound amplifier disposed in said chamber and comprising a solid wood neck secured within the chamber and having a curved bore therein, and a bell portion having its small end connected to the neck. and its large end secured in a wall of the chamber and consisting of a veneer blank bent to a rounded cross-sectional contour.

E. J MaeRUsoN, J. B. GRANT. 

